White blance and color temperature

White balance is when a camera removes unrealistic colors and makes things that appear white in person, appear white in a picture. It takes into account the pictures "color temperature" which is the relative coolness or warmth of white light. If the color balance is off, the areas that should be white might appear blue, green or orange.
Color temperature is the spectrum of light given off from a "blackbody", or an object that absorbs all incident light, with that surface temperature. Below is the spectrum:

To change or alter the effect the photographer should attach a different cast-removing filter every time they change lighting to traditional cameras. However, digital cameras don't require this change. A photographer can also make the white balance a custom one by making a neutral point or by having a pre-made white balance.